On Wed, Jun 2, 2021 at 2:04 PM Grant Taylor via NANOG <nanog@nanog.org> wrote: > On 6/2/21 4:35 AM, Jean St-Laurent via NANOG wrote: > > Maybe you can explore the in kernel feature call RP filter or reverse > > path filter. In router gear it's called uRPF. > > > > cat /proc/sys/net/ipv4/conf/default/rp_filter > > +100 to rp_filter
rp_filter is great until your network is slightly less than a perfect hierarchy. Then your Linux "router" starts mysteriously dropping packets and, as with allow_local, Linux doesn't have any way to generate logs about it so you end up with these mysteriously unexplained packet discards matching no conceivable rule in iptables... This failure has too often been the bane of my existence when using Linux for advanced networking. Regards, Bill Herrin -- William Herrin b...@herrin.us https://bill.herrin.us/
